Electric discharge device



Oct. 1, 1929. w. EVANS 1,729,715

ELECTRIC DISCHARGE DEVICE Filed Dec. 2, 1927 Inve ntom l e\ /L5 \X/. Evans, by fla @144 2 Hi5 Attohn ey,

Patented Oct. 1 1929 UNITED STATES.

PATENT oFFIcE LEWIS WILLIAM EVANS, rrrrs'EIEEn. riassac nusncrrs, ASSIGNOR 'I'O GENERAL 11112151021.RIC COMIZPANY, A CORPORATION o'E'nEw .Yonx

ELEorRIc, Disclaimer: DEVICE f Application filed necemiier 2, 1927. Serial as. 237,285.

' ber. Another object of the invention is to form one of the electrodes so that it may serve as a pelletcontainer. Another obyect of the invention is to shorten that portion of the pellet column which resides within the I porcelain container located below the elec-' trode on the side of the pellets. V

Other details of the invention will appear from the following specification in which' the means for accomplishing the re,

sults contemplated by the invention are fully set forth and claimed, reference beinghad to the accompanying drawing which shows a lightning arrester comprising the features of the invention.

The construction of thechamber 2, of the I casiii'gS enclosing said chamber, and of the upper portion ofthe arrester supported by said casing comprisingthe hoods stand 5,

theterminal 6 and the vupper electrode 7, isv

well known. The arrester is also provided with a porcelain tube 8which is hollow. Within the hollow portion, the usual column of pellets-9 is located. The lower portionot the arrester, that is, the porcelain member 8 with its hollow central portion and w1th the hood 10, together with the lower terminal element 11 is also well known. However, the lower electrode-12, as already indicated, forms one of the novel features of the in- 40 vention. This electrode as shown is in the form of an inverted cup provided with a flange 13 extending in a-,plane transverse to the axis of the electrode. The flange is, in turn provided with an upturned rim 14.

Theflange 13, as willbe seen, rests on the upper end. of the porcelainelement 8. It willalso be seen that the cup which 'forms the electrode 12 projects below the flange 13, therim of the cup which thus projects 9 below theflange snugly fittingthe opening at the upper end of a metal-, tube- 16 which extendsdown part wayin the porcelain tube 8. As clearly shown in the drawing, the porcelain element 3 rests-upon the rim .14 of the electrode 12, the'porcelain element 3 being providedwith a channel for receiving the said rim. It will be further seen that a sealing material such as cement 15 is used to bind the element 3 to the element8 and for sealing the space between the elements 3 and 8 6 adjoining the flange 13 and the rim 14: of the electrode 12. It will be-seen, therefore, that because of this construction andfbecause of the extension of the rim of the electrode .12 into the bore of the porcelain tube 8 so as to insure a close fit, the electrodechamber ,2 is insured against the leakage of any dustfrom the pellet chamber beneath and within 1 the electrode 12, by a path around the flange of electrode 12 into said'chamber 2. 79

It is commonly the case that with the ageing of the arrester the pellet column within the bore of the porcelain element'S shrinks and-therefore the pellet, columnshortens and the pellets gradually withdraw from the bottom of the inverted cup which forms the electrode 12. "lVith the old form of construction, this shrinkage of the pellet column was a very serious matter inasmuch as it affected the electrical connection between 80 the pellets and the electrode and in some instances. a gap was formed between the pellet column and the under side ofthe lower electrode. Obviously, therefore, with the new form of construction described and shown herein the .shrinkage of the column will merely result in theend of the column receding slightly possibly from the bottom of theinverted cup. Inasmuch as the cup is made of substantial depth, satisfactory electrical connection is preserved between the pellet column and the sides of the cup, not-. withstanding the shrinkage of the column, thereby insuring permanent connection between the column and the electrode, notwithstanding the use and age of the arrester.

It will-be understood that while Ihave disclosed my invention, in connection with a certain specific form of apparatus 1 do not wish to be limited to such form inasmuch as in View of the disclosure variations and modifications whichdo'not depart from the spirit of the invention or from the scope of the claims contained herein those versed in the art.

\Vhat I, claim as new and desire to secure by Letters Patent of the United States, is

1. In an electric discharge device, in com,- bination, a pair of electrodes forming a spark gap and a' resistance column connected in series with said gap,one of said electrodes being hollow, said column projecting into the hollow section of said hollow electrode and forming electrical connection'with the inner sides of the said hollow electrode whereby'connec tion may be maintained between the column and the hollow electrode notwithstanding a shrinkage of the columns 2. In a lightning arrester, in combination, a pair of electrodes forming a spark gap therebetween, a column of resistancematerial will readily occur to formed of'a mass of pellets, one of said el'ecw trodes being hollow and in the formof aninverted cup, said pellet column projecting into said cup whereby the column may be moied with respect tothe cup while maintaining electrical connection between the sides oft he column and the inside walls of the cup.

a pair of electrodes forming a spark gap therebetween, a column of resistance material, one of said electrodes being hollow and in the fOrIILQf an inverted cup,s aid resistance.

column projecting into said cup, whereby the column maybe moved with, respect to the cup. while maintaining electrical connection between the sides of thecolumn andthe inside walls of the cup, said cup being provided with vent any'dust from the pellet chamber passing into the spark gap chamber. I

4. In an electric'discharge device, in combination,'a pair of electrodes forming a spark gap, means for securin'g'said electrodes in adjusted relation with respect to each other, a column of resistance material, and means for supporting one endof said column in a fixed.

relation to one of said electrodes, the other end of said column being'in Variable physical relation but in permanent electrical connection withthe same electrode, whereby a circuit connection may be maintainedbetween the .columnand the latter electrode notwithstanding shrinkage of the column.

3. In a lightning arrester, in combination,

column of resistance material, and means for supporting one end of said column in a fixed relation to one of said electrodes, the other end of said column being in variable physical relation butin permanent electrical connection with the same electrode, whereby a cir-.

, respect to each other, whereby dust from the resistance column is prevented from passing from thecolumn to the-gap.

- 6. In'a lightning arrester, in combination, a pair of electrodes forming a spark gap therebetween, a column of resistance material, one of said electrodes being hollow and in the form of an inverted cup, saidresistan'ee col- 'umn projecting into said cup, whereby the column may be moved with respect to the cup while maintaining electrical connection be tween the sides of the column and the inside walls of the cup, a tube enclosing the lower part of said column, said cup being provided -with a flange extending transverse to the axis of the cup','a chamber enclosing the spark gap and a chamber enclosmgsald column, the column chamber being formed by the hollow electrodeand the tube, said flange forming a partition between .the' .two chan'ibers, and

means-for sealing the chambers from eacl other about said flange.

In witnesswhereof, I have hereunto set my hand this 29th day of November, 1927.

L. WILLIAM 'EVANS.

5. In an electric discharge device,.in-com- "bination, a pair'of electrodes forming a spark gap, means for securing said electrodes in adjusted relation with respect to each other, a 

